• Colour D - The highest colour grade attributed to a diamond, meaning that the stone is completely colourless (white). They are extremely rare and command the highest prices.
• ● Colour E - Even though E stones are slightly cheaper than D stones, the difference is often only visible to an expert gemmologist using master stones as a comparison.
• ● Colour F - Again the difference between E and F is only visible to an expert. F grade stones are the lowest and least expensive of the premium colours.
• ● Colour G - Nearly colourless, especially once set in jewellery. G graded stones represent excellent value for money.
• ● Colour H - Generally considered the watershed between colourless diamonds and slightly tinted diamonds. They appear totally white or colourless when not compared with higher graded stones.
• ● Colour I - Although slightly tinted, I graded stones may appear colourless once set in jewellery. A great option for maximising your budget.
• ● Colour J- Very slightly tinted diamonds that are suitable for setting in yellow gold jewellery, as the colour will become less visible.
• ● Colour K- Once again, the tint in K coloured diamonds will reduce when set in yellow gold jewellery.
• ● Colour L- Faint yellow hues are more obvious in L graded diamonds. For this reason, several jewellers won't stock grades below L.

Colour is more visible in larger diamonds. So if you're buying a diamond under 1 carat, you might only need a stone graded I, J or K. Then again, diamonds over 1 carat should be H colour-graded or higher otherwise a tint could be visible.

You will also find that certain fancy-shaped diamonds hide colour better than others and can cost up to 25% less than the most desirable round-cut diamond.

If your diamond is going to be set in a precious metal like 18 carat yellow or rose gold, you should consider a diamond with a slightly lower colour grade. The warmer colour tones of these metals will highlight the bright white appearance of the diamond rather than any perceivable tint.

You may even decide that colour is a good thing. After all, diamonds occur in the natural rainbow spectrum of colours - red, orange, yellow, green, blue, pink, purple, and more. Around 1 in every 10,000 diamonds possess natural colour, and the more intense the colour, the more valuable the diamond.

Fancy-coloured diamonds are graded on a separate colour scale and can be even more valuable than white diamon

• With premium colourless diamonds, the differences between D and G graded stones are barely visible but can provide 20-40% better value. D graded stones tend to be bought by investors or diamond aficionados.
• Seeing as H graded diamonds sit on the fence between premium colourless and tinted diamonds, they offer superb value. Unless compared side-by-side with a wider diamond, you will struggle to see any visible yellow or brown tint either.
• With I and J graded stones, you should only be able to detect slight yellow or brown tints when viewed from multiple angles. When viewed face down from the top, they appear white.
• K and L graded stones are still acceptable on a GIA certificate when it comes to tint. However, it is recommended to set these diamonds in yellow or rose gold jewellery to make the diamond appear less tinted.